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https://www.gov.scot

Performance

· 17 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
96
GRADE
A
FIX
0
REVIEW
3
PASS
12
INFO
2

Performance-focused optimization plan with CWV assessment, top offenders, and time estimates

Mobile Desktop
75
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
95
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
100
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
100
SEO Measures basic SEO optimizations: meta tags, crawlability, link text, and mobile friendliness.

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

1.81 s

Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.

1.96 s

Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.

0 ms

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.633

Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.

1.81 s

Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.

1.96 s

Page Load Progression

375 ms
750 ms
1.1 s
1.5 s
1.9 s
2.2 s
2.6 s
3.0 s
Checks
17
12 PASS 3 REVIEW
B
Image Optimization
4 images, 0 KB saveable
REVIEW
4 images, 0 KB saveable
Info::
All images are well-optimized
4 images 134 KB
0 oversized -0 KB
4 legacy format
0 missing dimensions CLS risk
B
JS Execution Cost
571ms total JS execution
REVIEW
571ms total JS execution
Warning::
https://www.gov.scot/: 298ms CPU time
Info::
Unattributable: 183ms CPU time
Info::
https://www.gov.scot/webfiles/1776248299365/assets...: 90ms CPU time
Info::
Third-party scripts: 183ms (32% of total)

Main Thread Breakdown

Other 36% Style & Layout 32% Script Evaluation 16% Rendering 8% Parse HTML & CSS 7%
ScriptTotalScriptingParse/CompileParty
https://www.gov.scot/298ms5ms1ms1st
Unattributable183ms11ms0ms3rd
https://www.gov.scot/webfiles/1776248299365/assets/scripts/global.js90ms56ms1ms1st
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
Page Weight Budget
287 KB transferred, 20 requests
PASS
287 KB transferred, 20 requests
Info::
Page weighs 718 KB (287 KB transferred)
Info::
20 HTTP requests
Info::
Estimated 0.06 g CO2 per page load
287 KB / 2.4 MB budget
287 KB transferred
20 requests
0.06 g CO2 per page load
Images 133.9 KiB 47%
JavaScript 45.4 KiB 16%
CSS 43.9 KiB 15%
Fonts 36.7 KiB 13%
Other 16.1 KiB 6%
HTML 11.0 KiB 4%
Other 504 B 0%
0 2.4 MB 4.9 MB
Under budget
A+
Third-Party Impact
16% third-party, 0 ms blocking
PASS
16% third-party, 0 ms blocking
Info::
Third-party code accounts for 16% of page weight (46.0 KiB of 287.5 KiB)
Info::
Third-party blocking time is low (0 ms)
84%
16%
First-party Third-party
A+
Text Compression
All text resources are compressed
PASS
All text resources are compressed
Info::
All text resources are compressed
All text resources are properly compressed.
A+
Font Loading
1 fonts (37 KB)
PASS
1 fonts (37 KB)
Info::
1 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

1

37 KB total

Render-blocking

0

of 1

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 500 ms 1.0 s 1.5 s 2.0 s FCP 1.8 s LCP 2.0 shttps://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3yUBHMdazQ.woff2KFO7CnqEu92Fr1ME7kSn66a... https://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3yUBHMdazQ.woff2 — 36.7 KiB — 49 ms — font-display: swap
KFO7CnqEu92Fr1ME7kSn66a... woff2 swap
Size 37 KB
Load time 49 ms
Start 177 ms
Risk FOUT — text flashes from fallback to web font
Optimization checklist
  • Preload critical fonts (priority=high)
  • Use woff2 format for all fonts
  • Set font-display to swap, optional, or fallback
  • Subset large fonts (≤100 KB each)
A+
JS Bundles
7 scripts, 23 KB unused
PASS
7 scripts, 23 KB unused
Warning::
https://www.gov.scot/webfiles/1776248299365/assets...: 23 KB unused (72%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 23 KB
23 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.gov.scot/webfiles/1776248299365/assets/scripts/global.js33 KB23 KB (72%)✓1st
https://www.gov.scot/webfiles/1776248299365/assets/scripts/datalayer.js1 KB—✓1st
https://www.gov.scot/webfiles/1776248299365/assets/scripts/gtm.js2 KB—✓1st
https://www.gov.scot/webfiles/1776248299365/assets/scripts/js-enabled.js1 KB—✓1st
https://www.gov.scot/webfiles/1776248299365/assets/scripts/home.js1 KB—✓1st
https://www.gov.scot/assets/scripts/vendor/plausible/script.file-downloads.outbound-links.js3 KB—✓1st
https://www.gov.scot/assets/scripts/vendor/svgxuse.min.js3 KB—✓1st

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

A+
Resource Caching
All resources properly cached
PASS
All resources properly cached
Info::
No caching issues found
All static resources have appropriate caching headers.
A+
Critical Rendering Path
No render-blocking resources
PASS
No render-blocking resources
Info::
No render-blocking resources detected
A+
Resource Hints
No optimization needed
PASS
No optimization needed
Info::
No resource hint issues
A+
Page Weight Inventory
20 resources · 287 KB · 23 KB savings available
PASS
20 resources · 287 KB · 23 KB savings available
Info::
Within 1MB page-weight target
Got: 287 KB
Info::
4 third-party resources (16% of weight)
20 resources · 287.5 KiB · 4 third-party Within 1MB page-weight target
Image 52% · 150.0 KiB
JavaScript 16% · 45.4 KiB
CSS 15% · 43.9 KiB
Font 13% · 36.7 KiB
Document 4% · 11.0 KiB
Other 0% · 504 B

~23.3 KiB of savings available

Remove unused JavaScript: 23.3 KiB
A+
Render-Blocking Resources
No render-blocking resources detected
PASS
No render-blocking resources detected
Info::
No render-blocking resources detected in <head>
A+
Third-Party Resources
No third-party resources detected
PASS
No third-party resources detected
A+
HTTP Caching
max-age=300 (5 minutes)
PASS
max-age=300 (5 minutes)
Info::
Cache-Control header is set
Got: public, max-age=300, s-maxage=60
Info::
Effective TTL: 5 minutes (max-age=300)
Info::
CDN TTL: 1 minute (s-maxage=60)
Info::
No ETag or Last-Modified header
Conditional requests (304 Not Modified) are not possible without validators.
Cache-Control

public, max-age=300, s-maxage=60

DirectiveValueMeaning
public—Any cache may store this response
max-age300Cache for 5 minutes
s-maxage60CDN caches for 1 minute
Effective TTL: 300 seconds
Network Waterfall
20 requests over 313ms
INFO
0 ms 500 ms 1.0 s 1.5 s 2.0 s FCP 1.8 s LCP 2.0 shttps://www.gov.scot// https://www.gov.scot/ — 200 — 11.0 KiB — 19 ms — h2https://www.gov.scot/webfiles/1776248299365/assets/scripts/datalayer.js/webfiles/1776248299365/assets/scri... https://www.gov.scot/webfiles/1776248299365/assets/scripts/datalayer.js — 200 — 1.3 KiB — 18 ms — h2https://www.gov.scot/webfiles/1776248299365/assets/scripts/gtm.js/webfiles/1776248299365/assets/scri... https://www.gov.scot/webfiles/1776248299365/assets/scripts/gtm.js — 200 — 2.2 KiB — 20 ms — h2https://www.gov.scot/webfiles/1776248299365/assets/css/main.css/webfiles/1776248299365/assets/css/... https://www.gov.scot/webfiles/1776248299365/assets/css/main.css — 200 — 35.1 KiB — 22 ms — h2https://maxcdn.bootstrapcdn.com/font-awesome/4.4.0/css/font-awesome.min.cssmaxcdn.bootstrapcdn.com/font-awesom... https://maxcdn.bootstrapcdn.com/font-awesome/4.4.0/css/font-awesome.min.css — 200 — 6.5 KiB — 84 ms — h3https://fonts.googleapis.com/css?family=Roboto:100,300,400,700,400italic&display=swapfonts.googleapis.com/css?family=Rob... https://fonts.googleapis.com/css?family=Roboto:100,300,400,700,400italic&display=swap — 200 — 2.4 KiB — 96 ms — h2https://www.gov.scot/webfiles/1776248299365/assets/scripts/js-enabled.js/webfiles/1776248299365/assets/scri... https://www.gov.scot/webfiles/1776248299365/assets/scripts/js-enabled.js — 200 — 956 B — 18 ms — h2https://www.gov.scot/assets/images/logos/scotgovlogo.svg/assets/images/logos/scotgovlogo.sv... https://www.gov.scot/assets/images/logos/scotgovlogo.svg — 200 — 2.4 KiB — 18 ms — h2https://www.gov.scot/binaries/content/gallery/featureditems/bank-holidays-png/bank-holidays-png/govscot%3Alargethreecolumnsdoubled/binaries/content/gallery/featuredi... https://www.gov.scot/binaries/content/gallery/featureditems/bank-holidays-png/bank-holidays-png/govscot%3Alargethreecolumnsdoubled — 200 — 5.1 KiB — 57 ms — h2https://www.gov.scot/webfiles/1776248299365/assets/scripts/global.js/webfiles/1776248299365/assets/scri... https://www.gov.scot/webfiles/1776248299365/assets/scripts/global.js — 200 — 33.0 KiB — 10 ms — h3https://www.gov.scot/webfiles/1776248299365/assets/scripts/home.js/webfiles/1776248299365/assets/scri... https://www.gov.scot/webfiles/1776248299365/assets/scripts/home.js — 200 — 1.3 KiB — 39 ms — h3https://www.gov.scot/binaries/content/gallery/featureditems/costofliving-support-work-jpeg/costofliving-support-work-jpeg/govscot%3Alargethreecolumnsdoubled/binaries/content/gallery/featuredi... https://www.gov.scot/binaries/content/gallery/featureditems/costofliving-support-work-jpeg/costofliving-support-work-jpeg/govscot%3Alargethreecolumnsdoubled — 200 — 12.6 KiB — 49 ms — h3https://www.gov.scot/assets/scripts/vendor/plausible/script.file-downloads.outbound-links.js/assets/scripts/vendor/plausible/sc... https://www.gov.scot/assets/scripts/vendor/plausible/script.file-downloads.outbound-links.js — 200 — 3.2 KiB — 9 ms — h3https://www.gov.scot/binaries/content/gallery/featureditems/council-elections.jpg/council-elections.jpg/govscot%3Amediumtwelvecolumnsdoubled/binaries/content/gallery/featuredi... https://www.gov.scot/binaries/content/gallery/featureditems/council-elections.jpg/council-elections.jpg/govscot%3Amediumtwelvecolumnsdoubled — 200 — 113.9 KiB — 131 ms — h3https://www.gov.scot/assets/scripts/vendor/svgxuse.min.js/assets/scripts/vendor/svgxuse.min.... https://www.gov.scot/assets/scripts/vendor/svgxuse.min.js — 200 — 3.4 KiB — 11 ms — h3https://www.gov.scot/webfiles/1776248299365/assets/images/icons/icons.stack.svg/webfiles/1776248299365/assets/imag... https://www.gov.scot/webfiles/1776248299365/assets/images/icons/icons.stack.svg — 200 — 3.4 KiB — 11 ms — h3https://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3yUBHMdazQ.woff2fonts.gstatic.com/s/roboto/v51/KFO7... https://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3yUBHMdazQ.woff2 — 200 — 36.7 KiB — 49 ms — h3https://plausible.io/api/eventplausible.io/api/event https://plausible.io/api/event — 202 — 504 B — 95 ms — h2https://www.gov.scot/favicon.ico/favicon.ico https://www.gov.scot/favicon.ico — 200 — 10.1 KiB — 35 ms — h3https://www.gov.scot/favicon-32x32.png/favicon-32x32.png https://www.gov.scot/favicon-32x32.png — 200 — 2.5 KiB — 9 ms — h3
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
32% of JavaScript execution is third-party
First-party Third-party 183ms · 0KB · €2/mo
Unattributable
Other
Optional
Execution 183ms
Transfer 0 KB
Monthly Cost €2/mo

How third-party costs are calculated

All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.

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